In cable television (CATV) networks, many network components (modulators, including quadrature amplitude modulation (QAM) modulators, transmitters, receivers, amplifiers) often provide a separate “test point” port, which is typically exclusively an output port, and typically not an input or dual input/output port. This test point is to verify levels at various frequencies, at a particular point in the CATV network, and thus to verify signal presence and the signal levels at various frequencies. This level verification process is typically done by hooking of a spectrum analyzer to a test point, in order to read levels/slope versus frequency. QAM modulators also can provide such a test point port.